I feel like I'm posting the same thing over and over as study after study finds the same or similar results. Bottom line: sitting much is bad for health, so get up and move (walks are good). The more you move or exercise, the better for health.
From Science Daily: Sitting for long periods increases risk of disease and early death, regardless of exercise
The amount of time a person sits during the day is associated with a higher risk of heart disease, diabetes, cancer, and death, regardless of regular exercise, according to a review study.
"More than one half of an average person's day is spent being sedentary -- sitting, watching television, or working at a computer," said Dr. David Alter, Senior Scientist, Toronto Rehab, University Health Network (UHN), and Institute for Clinical Evaluative Sciences. "Our study finds that despite the health-enhancing benefits of physical activity, this alone may not be enough to reduce the risk for disease." The meta-analysis study reviewed studies focused on sedentary behaviour.
The authors found the negative effects of sitting time on health, however, are more pronounced among those who do little or no exercise than among those who participate in higher amounts of exercise."The findings suggest that the health risk of sitting too much is less pronounced when physical activity is increased," said Biswas.
In the interim, Dr. Alter underlines strategies people can use to reduce sitting time. The target is to decrease sedentary time by two to three hours in a 12-hour day...For example, at work, stand up or move for one to three minutes every half hour; and when watching television, stand or exercise during commercials."